1. Technical Field
The present disclosure relates to a semiconductor integrated circuit, and more particularly, to a source driver provided in a display device that displays an image and a bias current adjusting method thereof.
2. Related Art
With the development of a communication technology, the use of display devices has rapidly increased. The display devices are mainly used as large screens used in televisions or small screens used in cellular phones.
The display device includes a display panel that displays an image and a plurality of drivers that drive the display panel, wherein the plurality of drivers include source drivers and gate drivers. The source drivers and the gate drivers are manufactured as semiconductor integrated circuits, are packaged, and then are mounted in the display device. The source driver is tested for various parameters at a wafer level or a package level in order to detect a defect occurring by the reason of a design or a manufacturing process or to evaluate operation characteristics. Among various parameters, one is a bias current. The bias current may be provided to an internal output buffer of the source driver, thereby having an influence on the analog output of the source driver.
The display panel includes a plurality of source drivers, wherein deviation of a bias current may exist for each source driver. The deviation of the bias current may occur by the difference of semiconductor manufacturing environments for each source driver. When the deviation of the bias current for each source driver is large, a dimming phenomenon may occur in the display panel by output deviation between the source drivers.
Therefore, the source driver should be manufactured such that the deviation of the bias current is not large. In a test process, a source driver, in which the bias current deviates from a prescribed range, may be determined as a defect, and the source driver determined as a defect may be discarded without being applied to products.
As described above, the defect of the source driver by the bias current deteriorates the yield of the source driver and increases the manufacturing cost.